Drill-chuck.



L. S. WHITEHBAD.

DRILL CHUCK.

APPLIATION FILED JUNE 4, 1910. 990,087. Patented Apr. 18, 1911.

v 11 5' Z a ,e 7` d zo UNITED sTATEs LEo s. WHITEHEAD, or WHEELING, WEST VIRGINIA.

DRILL-CHUCK.

Specilcation of Letters Patent.

Patented Apr. 18, 1911.

Application led June 4, 1910. Serial No. 565,072.

To all 'whom 'it may concern: l

#Be it known that I, LEO S. WHITEHEAD, a citizen of the United States, residing at Wheeling, in the county ofOhio and State of West Virginia, have invented new and useful Improvements in Drill-Chucks, of which the following is a specification.

The present invention has reference to improvements in -drill chucks and tapwrenches, and it comprehends generally the production of an implement wherein the tool holder and the head of the stock are constructed as to coperate in clamping the tool inplace when the clamping sleeve is turned in the proper direction. It further, and more especially, resides in the provision of a thimble which is Iinterposed between the sleeve above referred to and the front ends of thefjaws of the tool holder, and is designed both to coact therewith in effecting the requisite clamping action of said jaws and to center vand maintain. the latter in equidistant relation.

A structural embodiment of the invention is illustrated in the' accompanying drawing, wherein:

' Figure 1 is a longitudinal sectional view of the improved implement, showing the clamping jaws in contracted position. Fig. 2 is a similar View, showing said jaws expanded. Figs. 3 and 4 are detail side ele= vations of the stock and sleeve, respectively. Fig. 5 is a similar'view of the tool holder. Fig. 6 is an end view ofFig. 5. Fig. 7 is a perspective view of the thimble.` In said drawings, A and B indicate, respectively, the stock and tool holder, C the clamping sleeve and D the thimble. The yelement A comprises, essentially, a shank portion 1, anda head consisting of a cylindrical outer portion 2 and 7a frusto-conical or tapered inner or connectingportion 3, the former port-ion. of said head being exte-l riorly threaded. This elementffis substantially hollow and receives within the bore of its shank the shank portion 4 of the tool holder B, the inner end of shank-4 terminating short of that of said bore so as to permit the interposition of a suitable expansible c`oil spring 5 within the intervening space, which sprin tends to normally force the holder outwar ly, as will be understood. The toolI holder is likewise approximately hollow-and is split longitudinally at equidistant intervals to provide a plurality of legs 6, the outer jaw portions 7 of which are thickened. The end portions 7 and 72 of these jaws are reversely ytapered or beveled, the inclination vof the inner end portions 72 being the same as that of the tapered portion 3 of the stock head. Saidvjaws normally maintain an open or expanded position due to the inherent resiliency ofthe metal from which the holder is constructed. To close or contact the jaws, so as to cause them to grip the shank of a drill, tap, or other suitable tool, (not shown), the sleeve Gand. thimble D are provided. The first element is, in

the main, of conventional type and com prises van interiorl threaded cylindrical inner portion 8, an a frusto-conical outer portion or mouth 9, the former portion fitting upon the corresponding cylindrical portion 2 of the stock head. Thimble D is also frusto-,oonicah its taper or angularity corresponding to that of the outer end portions of jaws 7 as well as to that of the mouth portion 9 of the sleeve, whereby it may be interposed between said portions in the manner shown in Figs. 1 and 2. Its inner surface or wall is formed at equidistant points with transverse depressions 10 corresponding in number. to the number of jaws 7 and adapted to receive the noses of said jaws, the provision of these depressions tending to insure the accurate centering of the jaws and to maintain them in' equidistant relation.

The stock shank l is formed with a terminal tang 11 of any desired construction.

In assembling the various parts, the spring 5 is rst introduced into the stock bore, after which the shank of the tool holder is inserted therein. The thiinble is next fitted within the sleeve, fitting in the seat produced by the mouth portion 9, and

.said sleeve-then screwed onto the cylindricalV outer portion 2 of the stock head. The shank of the proper tool may then be introduced through the alining open ends of the sleeve and thimble into the space between the inner faces of the clamping jaws 7, the latter being at that time in the open orexpanded position shown in Fig. 2. T0 clamp the tool shank in place, it is only necessary to tighten the sleeve upon the threaded portion of the stock head in the ordinary manner, whereupon the engagement of the thimble with the front ends 7 of the jaws lwill Gradually close the latter, and will also movement, the coaction between the inclined *i t portion 3 of the stock head and the rear:w

or inner ends 7 2 of the jaws will likewise cause said jaws to bind against the tool shank, thus supplementing and materially assisting the afore-mentioned closing action eiected by the coaction between the thimble and the jaw ends 7. When the sleeve is turned in the opposite direction, the jaws W1ll be free to resume their normal position,

normally-expanded jaws having their free ends tapered; a clamping sleeve rotatably fitted on said stock; and a clamping member interposed between the outer endr of the sleeve and said jaw ends and having a conical inner face formed with depressionsI wherein the latter' are received, for center]- ing the same and closing them when said sleeve is rotated in one direction.

, 2. A chuck comprising, in combination, a substantially, hollow stock; a tool holder inserted in the bore thereof and formed with normally-expanded jawsvhaving their free ends tapered; a clamping sleeve rotatably fitted on said stock; and a conical clamping thimble interposedabetween the outer end of the slee've and said jaw ends and formed with depressions wherein the latter are received for centering the same and closing them when said sleeve is rotated in onel direction. f

In testimony whereof `I have hereunto set my hand in presence of two subscribing Witnesses. I

LEO s. WI-IrrEHnAD.

Witnesses Y JOHN R. ARBENZ, E. BALZER. 

